static int lp_reset(int minor)
{
outb_p(LP_PSELECP, LP_C(minor));
udelay(LP_DELAY);
outb_p(LP_PSELECP | LP_PINITP, LP_C(minor));
return LP_S(minor);
}
static inline int lp_char_polled(char lpchar, int minor)
{
int status, wait = 0;
unsigned long count = 0;
struct lp_stats *stats;
do {
status = LP_S(minor);
count ++;
if(need_resched)
schedule();
} while(!LP_READY(minor,status) && count < LP_CHAR(minor));
if (count == LP_CHAR(minor)) {
return 0;
/* we timed out, and the character was /not/ printed */
}
outb_p(lpchar, LP_B(minor));
stats = &LP_STAT(minor);
stats->chars++;
/* must wait before taking strobe high, and after taking strobe
low, according spec. Some printers need it, others don't. */
while(wait != LP_WAIT(minor)) wait++;
/* control port takes strobe high */
outb_p(( LP_PSELECP | LP_PINITP | LP_PSTROBE ), ( LP_C( minor )));
while(wait) wait--;
/* take strobe low */
outb_p(( LP_PSELECP | LP_PINITP ), ( LP_C( minor )));
/* update waittime statistics */
if (count > stats->maxwait) {
#ifdef LP_DEBUG
printk(KERN_DEBUG "lp%d success after %d counts.\n",minor,count);
#endif
stats->maxwait = count;
}
count *= 256;
wait = (count > stats->meanwait)? count - stats->meanwait :
stats->meanwait - count;
stats->meanwait = (255*stats->meanwait + count + 128) / 256;
stats->mdev = ((127 * stats->mdev) + wait + 64) / 128;
return 1;
}
static inline int lp_char_interrupt(char lpchar, int minor)
{
int wait;
unsigned long count = 0;
unsigned char status;
struct lp_stats *stats;
do {
if(need_resched)
schedule();
if ((status = LP_S(minor)) & LP_PBUSY) {
if (!LP_CAREFUL_READY(minor, status))
return 0;
outb_p(lpchar, LP_B(minor));
stats = &LP_STAT(minor);
stats->chars++;
/* must wait before taking strobe high, and after taking strobe
low, according spec. Some printers need it, others don't. */
wait = 0;
while(wait != LP_WAIT(minor)) wait++;
/* control port takes strobe high */
outb_p(( LP_PSELECP | LP_PINITP | LP_PSTROBE ), ( LP_C( minor )));
while(wait) wait--;
/* take strobe low */
outb_p(( LP_PSELECP | LP_PINITP ), ( LP_C( minor )));
/* update waittime statistics */
if (count) {
if (count > stats->maxwait)
stats->maxwait = count;
count *= 256;
wait = (count > stats->meanwait)? count - stats->meanwait :
stats->meanwait - count;
stats->meanwait = (255*stats->meanwait + count + 128) / 256;
stats->mdev = ((127 * stats->mdev) + wait + 64) / 128;
}
return 1;
}
} while (count++ < LP_CHAR(minor));
return 0;
}
static inline int lp_write_interrupt(unsigned int minor, const char * buf, int count)
{
unsigned long copy_size;
unsigned long total_bytes_written = 0;
unsigned long bytes_written;
struct lp_struct *lp = &lp_table[minor];
unsigned char status;
do {
bytes_written = 0;
copy_size = (count <= LP_BUFFER_SIZE ? count : LP_BUFFER_SIZE);
memcpy_fromfs(lp->lp_buffer, buf, copy_size);
while (copy_size) {
if (lp_char_interrupt(lp->lp_buffer[bytes_written], minor)) {
--copy_size;
++bytes_written;
lp_table[minor].runchars++;
} else {
int rc = total_bytes_written + bytes_written;
if (lp_table[minor].runchars > LP_STAT(minor).maxrun)
LP_STAT(minor).maxrun = lp_table[minor].runchars;
status = LP_S(minor);
if ((status & LP_POUTPA)) {
printk(KERN_INFO "lp%d out of paper\n", minor);
if (LP_F(minor) & LP_ABORT)
return rc?rc:-ENOSPC;
} else if (!(status & LP_PSELECD)) {
printk(KERN_INFO "lp%d off-line\n", minor);
if (LP_F(minor) & LP_ABORT)
return rc?rc:-EIO;
} else if (!(status & LP_PERRORP)) {
printk(KERN_ERR "lp%d printer error\n", minor);
if (LP_F(minor) & LP_ABORT)
return rc?rc:-EIO;
}
LP_STAT(minor).sleeps++;
cli();
outb_p((LP_PSELECP|LP_PINITP|LP_PINTEN), (LP_C(minor)));
status = LP_S(minor);
if ((!(status & LP_PACK) || (status & LP_PBUSY))
&& LP_CAREFUL_READY(minor, status)) {
outb_p((LP_PSELECP|LP_PINITP), (LP_C(minor)));
sti();
continue;
}
lp_table[minor].runchars=0;
current->timeout = jiffies + LP_TIMEOUT_INTERRUPT;
interruptible_sleep_on(&lp->lp_wait_q);
outb_p((LP_PSELECP|LP_PINITP), (LP_C(minor)));
sti();
if (current->signal & ~current->blocked) {
if (total_bytes_written + bytes_written)
return total_bytes_written + bytes_written;
else
return -EINTR;
}
}
}
total_bytes_written += bytes_written;
buf += bytes_written;
count -= bytes_written;
} while (count > 0);
return total_bytes_written;
}